<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="root">
        
    </div>

    <script src="https://unpkg.com/react@18/umd/react.development.js" crossorigin></script>
    <script src="https://unpkg.com/react-dom@18/umd/react-dom.development.js" crossorigin></script>
    <script src="https://unpkg.com/babel-standalone@6.15.0/babel.min.js"></script>

   
    <script type="text/babel">
        class DivElement extends React.Component{
            
            state = {
                count:0
            };
            constructor(props){
                super(props);          
            }
            handleClick = (e) => {
                console.log(e.target);
                // 1. 完成对指定属性值的修改
                // 2. 完成对绑定节点的渲染
                this.setState({
                    count:this.state.count+1
                });
                console.log("click",this.state.count);
            }
            render(){
                return <div>
                        <input type="button" value="++" onClick={this.handleClick} />
                        <input type="button" value="--" onClick={this.handleClick} />
                        <span>计数器：{this.state.count},{this.props.cnt}</span>
                    </div>
            }
        }
        const root = ReactDOM.createRoot(document.getElementById("root"));
        root.render(<DivElement cnt="0"></DivElement>);
    </script>
</body>
</html>